Data centers can support cleaner, cooler cities

Gavin Allen: As the AI boom continues, data centers will need more electric power. What does this mean for cities?

Susanna Kass, Stanford Energy Fellow / Co-Founder, InfraPrime

Susanna Kass: Cities should treat it as a wake-up call. Plans to build thousands of gigawatt-scale AI data centers were announced in 2025. Most will come online between 2026 and 2028. In a 2024 report, the International Energy Agency projected that data centers' power demand will grow at a compound annual rate of about 15% in the near term — equivalent to adding the total electricity consumption of a country like Sweden, or even Germany, to the world's grids.

Gavin Allen: How will cities cope with this surging power demand?

Susanna Kass: The keys are to shift data centers from fossil-based power to clean energy, and to recover and re-use heat waste so that it becomes a resource, rather than a byproduct.

Data centers run 24 hours a day, and their cooling systems continuously generate warm water that can be captured and pumped through underground pipes to serve nearby buildings such as offices, residences, or factories. This "district heating" approach is already well established in the Nordic countries. It serves about 40% of the roughly 100,000 homes in Espoo, Finland, a city near Helsinki. In Sweden, facilities south of Stockholm feed recovered heat waste into systems serving about 100,000 homes. These cities are turning heat waste from data servers into a primary energy source.

Gavin Allen: You've helped pioneer "Absolute Zero" data center architectures, which eliminate fossil fuels, diesel backup, and the need for carbon offsets. What's different about this approach?

Susanna Kass: Most data centers today aim for Net Zero. They reduce emissions where they can through efficiency and cleaner power, then account for the remainder at year-end using offsets or clean-energy credits. Absolute Zero goes further, focusing on the hour-by-hour alignment between a data center's energy use and its real-world emissions impact.

Gavin Allen: What's preventing more widespread adoption of Absolute Zero?

Susanna Kass: The biggest barrier is mindset: sticking with conventional approaches rather than reinventing data centers around total social cost of ownership and long-term impact.

Regulation can also become a barrier when government policy, utility incentives, and private-sector innovation are misaligned, slowing the adoption of cleaner, more flexible data center designs. Often, the best case is that governments don't get in the way. Where utilities are government-owned, they can play the role of heat off-taker.

Gavin Allen: AI workloads increasingly require data centers to be located closer to cities. How should urban planners approach siting and zoning so that new facilities don't exacerbate urban heat islands?

Susanna Kass: Not every AI workload needs to be handled in the city. Some applications do require proximity to users to deliver a high quality of service — for example, when electric vehicles need to correlate GPS data with real-time local traffic conditions. For many other workloads, however, computing can be located elsewhere without affecting performance.

If data centers belong in or near cities, planners should integrate them as deeply as possible into the urban fabric. In Paris, for example, the Equinix PA10 data center — built near the site of the 2024 Olympics — supports a rooftop greenhouse that uses waste heat to grow strawberries and tomatoes. In Norway, Green Mountain routes waste heat from its data centers to a nearby lobster farm, where the warmed seawater provides the optimal 20°C environment the lobsters need. In both cases, data centers function not as isolated industrial sites, but as active contributors to local ecosystems.

Gavin Allen: How can next-generation data centers avoid adding to urban heat?

Susanna Kass: Data centers need to stop emitting waste heat into the environment. Instead, they should capture and recycle it, supporting district heating and cooling and reducing water use, in order to minimize environmental impact.

On the heating side, data centers are heat suppliers: heat generated by servers is absorbed by liquid circulating through the data center. Heat pumps then raise that temperature to a usable level, and the resulting hot water is piped to nearby buildings.

On the cooling side, data centers are cool-water consumers. But next-generation data centers are shifting toward "closed-loop" systems that recirculate the same water continuously, rather than drawing fresh supplies from the city. Combined with more targeted air cooling and liquid-to-chip technologies that deliver coolant directly to the center's hottest components, these designs improve efficiency, while reducing water consumption.

One promising direction is microfluidic cooling, which sends coolant through microscopic channels built directly into or just beneath the chip, where most of the heat is generated. By cooling the source of the heat rather than the surrounding hardware, data centers can remove heat more efficiently, and with less wasted energy.

Gavin Allen: You've argued that future data centers should generate their own clean power — what you call "Bring Your Own Power," or BYOP. Is this a viable large-scale strategy, or mainly a niche solution for larger operators?

Susanna Kass: Data centers shouldn't necessarily cut themselves off from the grid, but they should take responsibility for the power they consume. Instead of just contributing to the electricity load, they can help drive the build-out of cleaner, more resilient energy systems.

At scale, that means using their size and long-term planning horizons to anchor new clean power through long-term offtake agreements for wind, solar, and other firm clean sources. It also means investing in on-site energy capabilities, such as fuel cells, energy storage, and integrated heating and cooling systems, so operators have more control over when and how they draw electricity.

Gavin Allen: Urban heatwaves stress both electricity grids and cooling systems. What technical or architectural choices allow data centers to remain reliable — and even support local grids — during extreme heat events?

Susanna Kass: Heat resilience starts with precision. Increasingly, AI can be used to identify heat signatures in minute detail — down to individual chips and racks — allowing operators to cool only what actually needs cooling.

Rather than lowering the temperature of an entire room or rack, targeted cooling addresses the primary heat sources directly. It's the same principle as not turning on the air conditioning when you're not hot: most of the heat comes from specific components, so that's where cooling should be focused.

With sufficient data and monitoring, AI can also anticipate where heat will build up, enabling pre-emptive cooling before temperatures reach levels that affect performance. Liquid can be routed precisely to those hotspots, stabilizing temperatures under high thermal loads while reducing the energy that would otherwise be consumed by broad, chilled-water systems.

More broadly, resilience isn't something data centers design for only during emergencies. It's a 24/7 requirement. The same architectures that support precision cooling can also integrate with district heating and district cooling systems, giving cities more flexibility to manage energy demand — during extreme heat, extreme cold, and everything in between.

Gavin Allen: Looking ahead two or three years, what innovations give you confidence that cities can grow their digital infrastructure without accelerating heat stress or emissions?

Susanna Kass: I'm optimistic because we're entering an era in which digital transformation becomes fully electrified, and AI and internet technologies are woven into daily life in ways that improve safety and quality of life. The goal is a carbon-free economy where clean air and clean water are part of the baseline — and where digital systems are designed in a more symbiotic relationship with the environment.

In that future, cities become more circular by design. Data centers feed recovered waste heat into underground heat networks and connect to clean energy systems. They still exist within cities, but are blended into buildings and landscapes — providing reliable digital services without becoming a visible, environmental, or thermal burden.

Gavin Allen: Is there anything we haven't covered that you think city leaders, sustainability teams, or cloud users urgently need to understand?

Susanna Kass: Two thoughts. First, we need an open mindset. The biggest challenge isn't technology, economics, or regulation on their own — it's the willingness to think holistically and long-term, and to embrace new ideas so we can reach a carbon-free economy responsibly.

Second, we need to think in terms of future generations. Data centers are long-term investments that serve communities far beyond their own fences. The decisions we make today will shape cities for decades, which means cultivating future leaders, listening to new ideas, and collaborating across generations as we build the systems cities will depend on.

Susanna Kass is one of the most influential voices in cloud and hyperscale sustainability. She serves as a United Nations SDG Environmental Program Advisor, helping Google, Microsoft, Amazon Web Services (AWS), Meta, and Equinix align hyperscale growth with climate goals through the UN SDG Action Campaign. She has been recognized globally as a Top 10 Women in Data Center Leadership, and a multi-award recipient for climate innovation, featured by DatacenterDynamics, Data Centre Magazine, CIO Views Magazine, MSN, and World's Leaders® Magazine.

Five things every city should know about data centers

1. They’re becoming part of the urban heat equation. Data centers are now essential civic infrastructure — powering hospitals, transport, payments, and AI tools. But they also add to the demand placed on city power grids.
2. AI is pushing them closer to urban cores. Low-latency applications (real-time AI services, telemedicine, smart mobility) need compute power within milliseconds, drawing new facilities to the “metro-edge,” inside or just outside cities.
3. Their cooling needs shape local heat exposure. High-density compute racks require heavy cooling. Without efficiency standards and clean power, data centers can intensify waste heat, adding stress to local grids during extreme heat.
4. Their waste heat can be repurposed as useful energy. Modern data centers can channel surplus heat into local heating-and-cooling networks, greenhouses, or industrial processes — reducing overall energy waste and a city's total energy consumption.
5. Next-generation designs can boost resilience. Absolute Zero–style facilities generate on-premise clean power 24 hours a day. This reduces local emissions, eliminates the need for diesel generators, and can even provide backup support to the local grid during extreme-heat emergencies.

What “Absolute Zero” means for data centers

Most data centers today aim for Net Zero, meaning they reduce emissions as much as possible then offset what they can't eliminate, typically by buying renewable-energy certificates or investing in carbon projects elsewhere.

Absolute Zero goes much further. It means a data center does not emit carbon at all during operations—and in some cases can even remove CO₂ from the atmosphere. Nothing is balanced with offsets. Instead, emissions are eliminated or captured before they ever escape into the air.

Next-generation designs make this possible by using on-site clean power, such as advanced fuel cells running on green hydrogen or renewable natural gas. These systems avoid fossil fuels entirely. They capture any CO₂ emissions and reuse the heat they generate in ways that lower overall energy demand—for example, channeling it into nearby buildings or industrial processes that would otherwise need their own heating systems.

InfraPrime, a company co-founded by Susanna Kass, has helped pioneer modular "Absolute Zero" systems: self-contained clean-power units that can run 24/7 without the grid and even provide backup clean electricity during outages.

The goal: a data center that produces no emissions—ever.